How to Inoculate your FORIJ Woodworks Sawdust Fruiting Block 

FORIJ Woodworks Fruiting Blocks are fully sterilized, perfectly supplemented hardwood fruiting blocks used to grow hardwood-loving mushrooms using the spawn of your choice. Once inoculated, the blocks can be left to colonize and then fruited out in the comfort of your home. 

The block can be inoculated with grain spawn to be fruited out directly or used to inoculate logs. Here, we provide instructions on how to fruit culinary mushrooms straight from the FORIJ Hardwood Fruiting Blocks. You will need: 

  • Isopropyl alcohol or bleach
  • Disposable gloves
  • Scissors 
  • Impulse sealer  
  • Spawn. Shop FORIJ spawn here
  • Laminar flow hood (recommended)

If you would like to skip these steps you can purchase one of our Fruiting Kits with mushroom culture included and easily grow mushrooms right on your kitchen counter!  

  1. Start the process by wiping down your work surface with bleach or 70% isopropanol. Continue to wipe down your tools, recipient sterile grain bag, gloved hands. We recommend that you also perform all your inoculations in front of a sterile laminar flow hood to minimize the risk of contaminants entering your grow. 
  2. For grain spawn inoculations, loosen up your grain spawn bag and wipe down the grain spawn bag with an alcohol solution. Cut open the grain spawn bag, and quickly add the desired amount of grain spawn into your Woodworks sterile fruiting block bag--the more you add, the faster the colonization. We recommend a 10-20% ratio of grain spawn to fruiting block. This means that you can inoculate several Woodworks Fruiting Blocks per bag of grain spawn (1:6 to 1:10 is typical).
  3. Quickly close up both bags when finished using an impulse sealer and thoroughly shake up your newly inoculated fruiting block so that the mycelium-coated grains make as much contact with sawdust as possible.
  4. Let the bag sit at room temperature for 10-21 days, depending on the type of mycelium and the amount of grain spawn used to inoculate the block. Do not shake up the bag after inoculating - just let it take its course and colonize naturally. A fully colonized spawn bag is completely white (covered in mycelium). Keep in mind that the texture of the mycelium varies depending on the species. Lion’s mane, for example, has much finer mycelium than that of blue oyster. 


Fruiting - cutting and fruiting out your fruiting blocks 

Once your spawn block has fully colonized, it is ready to fruit! Fruiting requirements vary at this stage, most culinary mushrooms require a cut at the top of the bag or on the side to trigger fruiting. You will need:

  • Scalpel or sharp knife
  • Tape
  1. Using a scalpel, start by making a confident “X” slash (about 6 inches) on the surface of your fruiting block where you’d like your mushrooms to grow. Cutting the bag allows fresh oxygen to flow, which triggers fruiting. For pioppino and king oyster mushrooms, you should cut off the entire top of the bag. Depending on species, the pins will begin to grow 4-14 days after the cut is made, the mushrooms will grow quickly after pinning. 
  2. We recommend that home growers place their fruiting blocks close to a sink because it typically creates a more humid environment for mushrooms to grow in. Using a spray bottle, mist the opening of your block at least twice a day, more if you live in a dry environment. Ensure your block is placed somewhere with ambient light 12 hours a day, but not in direct sunlight. 
  3. You can tell your mushrooms are ready to harvest when the caps begin to flatten. When it is time to harvest, we recommend cutting the mushrooms off at the base of the stem, trying not to damage the fruiting block underneath. After you harvest your mushrooms, continue to spray as before because the blocks have the ability to produce. Watch closely for contamination, as older fruiting blocks are more prone to molding. It is well known that newer mycelial growth will take over the harvested portions of the block before the next flush. 

Please see Grow Kit FAQs for any questions regarding the fruiting stage. 


Enjoy your Mushrooms!